The pancreas is an organ that is made up of two very different types of tissue; endocrine and exocrine tissue. The endocrine tissue produces a well known hormone - insulin. The exocrine tissue produces digestive enzymes that are secreted into the intestinal tract to help digest food. We can see a few different issues with the pancreas, and in some cases, one disease can lead to another. Probably the most well known disease affecting the pancreas is diabetes. However, we can also see pancreatic insufficiency, acute and chronic pancreatitis, and of course, pancreatic cancer.
Diabetes. There are two types of diabetes in people and animals. Type I is when your pancreas just stops producing enough insulin, for many different reasons. Type II is when your pancreas is still producing insulin, but your cells are no longer functioning with the the normal amounts of insulin, so your pancreas has to produce more and more insulin, and eventually you reach a point where you need additional external insulin to get your cells to go through their normal processes. Type II diabetes is the most common type of diabetes that we see in cats, usually from being overweight. Type I diabetes can also occur in cats, but less commonly, and usually arises from chronic pancreatitis. Cats can also have a little of both types. The most common symptoms are eating more with losing weight, and drinking and urinating very large volumes.
Unlike people, cats do not tend to respond well to oral diabetic medications. They need insulin, and insulin needs to be given as an injection. "But I can't give my cat shots!" you say. You would be surprised at just how easy it is to give cats insulin shots. The needles are so tiny that most cats don't even notice them, and especially if you give your cat a treat while you are giving the injection, they may actually come tell you when it is time for a shot. We have had owners in all states of health, and some with only one working hand or arm give their cats insulin injections twice daily, and if they can do it, so can you.
Diet changes can also help reduce the amount of insulin you need to give your cat. Unlike diabetic dogs who do best on a high fiber diet, diabetic cats do best on a high protein low carb diet, and in some cases, with weight loss and a diet change, may even be able to go off of insulin. If your cat has Type I diabetes, they will be on insulin for life regardless, but they can live a long normal life with proper treatment.
Pancreatic insufficiency. This happens when the pancreas is not able to make enough digestive enzymes, and food goes through the intestinal tract not completely digested. This will result in a very potent smelling fluffy diarrhea. This can also increase likelihood of vomiting. The only way to treat this is give your cat supplemental digestive enzymes to help them digest their food. This is available in either pill form that you give to your cat immediately before feeding, or a powder that you can mix into moist food to 'pre-digest' it. It does make the food rather soupy, and not all cats will eat it that way. There is a blood test for pancreatic insufficiency, but for most cats we will diagnose it either by finding a very high amount of fat in the stool under the microscope, or by just trying treatment and seeing if they respond.
Pancreatitis. This can be either acute or chronic. No one knows for sure what causes acute pancreatitis in cats. In dogs it can be linked to a fatty meal, but that does not seem to be a causative factor in cats. Acute pancreatitis can result in intensive vomiting and nausea. This may also cause a temporary type I diabetes as a result because the pancreas is so inflamed that it has a hard time producing insulin. Acute pancreatitis is not easy to diagnose. There is a blood test that will test for elevated pancreatic enzymes specific to cats, but it does have some disadvantages. It is fairly costly, and it must be run while the pancreas is actively inflamed to get a diagnosis. Even then, there is a small chance it could come back negative when pancreatitis is present. A radiologist or experienced ultrasonagrapher may be able to see an enlarged pancreas on ultrasound, but your average veterinarian is not skilled enough to do this. The most likely test to give a definitive diagnosis is a biopsy, but that requires abdominal surgery. We will often rule out the other most common diseases, diagnose pancreatitis by default, and treat to see if there is a response to treatment. Treatment generally consists of antibiotics, pain reliever, anti-inflammatories (NOT steroids), and anti-nausea medication. Steroids are contraindicated if there is any suspicion at all of pancreatitis, as steroids are very prone to causing diabetes if pancreatis is present.
Once the inflammation of acute pancreatitis calms down, either on its own or with antibiotics and anti-inflammatories, there is the potential to develop chronic pancreatitis. Again, no one knows for sure why this is, but we will see a chronic low grade inflammation in the pancreas, which over time will result in scar tissue building up in the pancreas. We can also see a disorder called amyloidosis, which is more common in certain breeds of cats that can also result in low grade inflammation and scar tissue build up in the pancreas. This cannot be diagnosed without a biopsy, so we will often just see if there is response to treatment. With chronic pancreatitis we can either treat symptomatically or with preventative medications which can be costly, and some of which are only available in pill form.
If enough scar tissue builds up in the pancreas from pancreatitis, either acute or chronic, not only can it stop producing an adequate amount of insulin, resulting in Type I diabetes, it can also stop producing an adequate amount of digestive enzyme, which results in pancreatic insufficiency. If your cat has been a diabetic for any length of time, and suddenly starts having the large fluffy stinky diarrhea, our first thought will usually be pancreatic insufficiency as a result of chronic pancreatitis.
Pancreatic cancer is thankfully not a common cancer in cats even though we do see it on occasion. Pancreatic cancer is a highly malignant aggressive cancer. By the time we find it, it is pretty much always too late to have any significant impact with chemotherapy.